Renormalized dynamics in charge qubit measurements by a single electron transistor
arXiv:1010.4622 · doi:10.1016/j.physleta.2010.10.002
Abstract
We investigate charge qubit measurements using a single electron transistor, with focus on the backaction-induced renormalization of qubit parameters. It is revealed the renormalized dynamics leads to a number of intriguing features in the detector's noise spectra, and therefore needs to be accounted for to properly understand the measurement result. Noticeably, the level renormalization gives rise to a strongly enhanced signal-to-noise ratio, which can even exceed the universal upper bound imposed quantum mechanically on linear-response detectors.
6 pages, 5 figures
References in corpus (11)
- Quantum-Limited Measurement and Information in Mesoscopic Detectors
- Relaxation and Zeno effect in qubit measurements
- Spontaneous Relaxation of a Charge Qubit under Electrical Measurement
- Continuous quantum measurement with independent detector cross-correlations
- Calculation of the current noise spectrum in mesoscopic transport: an efficient quantum master equation approach
- Quantum Nondemolition Measurement of a Kicked Qubit
- Qubit measurements with a double-dot detector
- Quantum measurement characteristics of double-dot single electron transistor
- Weak Measurement of Qubit Oscillations with Strong Response Detectors: Violation of the Fundamental Bound Imposed on Linear Detectors
- Reduced dynamics with renormalization in solid-state charge qubit measurement
- Spin-dependent current noises in transport through coupled quantum dots